Variable diameter medical balloon

ABSTRACT

An apparatus for performing a medical procedure includes a balloon comprising an inflatable body. A first releasable or frangible connection is provided to maintain the body at a first diameter up to a first inflation pressure, and to release, such as by disconnecting, and thus allow the body to assume a second diameter, such as at a second inflation pressure greater than the first inflation pressure or upon a manual release of the connection by a clinician. Multiple releasable or frangible connections may be provided, including between portions (folds) of the inflatable body of the balloon. This disclosure also pertains to a non-compliant or semi-compliant balloon having a first inflation diameter corresponding to a first range of inflation pressures and a second inflation diameter corresponding to a second inflation pressure greater than the first range of inflation pressures.

INCORPORATION BY REFERENCE

This application is a continuation of U.S. application Ser. No.14/887,919 which is incorporated herein by reference. All publicationsand patent applications mentioned in this specification are hereinincorporated by reference to the same extent as if each individualpublication or patent application was specifically and individuallyindicated to be incorporated by reference.

BACKGROUND

Non-compliant medical balloons for performing angioplasty and othermedical procedures are known. U.S. Pat. No. 6,746,425 to Beckhamdiscloses a non-compliant medical balloon and methods for manufacturingthe balloon. U.S. Patent Application Publication No. US 2006/0085022 toHayes et al. discloses a non-compliant medical balloon having anintegral woven fabric layer and methods for manufacturing the balloon.U.S. Patent Application Publication No. US 2006/0085023 to Davies, Jr.et al. discloses a medical balloon having strengthening rods and methodsfor manufacturing the balloon. U.S. Patent Application Publication No.US 2006/0085024 to Pepper et al. discloses a non-compliant medicalballoon having an integral non-woven fabric layer and methods formanufacturing the balloon. U.S. Pat. No. 6,746,425 and Publication Nos.US 2006/0085022, US 2006/0085023 and US 2006/0085024.

During an intervention, the balloon is inserted into a vessel, typicallyon the end of a catheter, until the balloon reaches the area ofinterest. Adding pressure to the balloon causes the balloon to inflate.In one variation of use, the balloon creates an outwardly directed forcewhen inflated, which can be used to treat a variety of conditions.

As can be appreciated, different applications (such as for treatingdifferent vessels or parts of the body) may require the use of balloonshaving different diameters when inflated. Currently, manufacturers makemultiple balloons available for use with different inflation diameters,and the clinician must select the appropriate balloon under a given setof conditions. In some cases, the number of balloons available may bemore than twenty, ranging widely in diameter when inflated (e.g., from12-26 millimeters) for a variety of different vessel diameters. Thisclearly increases the demands on manufacturers to provide the fullvariety of balloons that might be required for use with different sizesof vessels (which can vary at the sub-millimeter level), and also addscomplexity to the selection process by the clinician given the largenumber of options available. While fully compliant balloons may be usedto provide a variety of diameters under different inflation pressures,this compliance makes such a balloon generally ineffective for providingthe treatment in the desired manner, especially where a significantforce is required.

Thus, it would be desirable to provide a single balloon that can beadjusted (including in situ) to treat a variety of vessel diameters inan effective and reliable manner.

SUMMARY OF THE DISCLOSURE

According to one aspect of the disclosure, an apparatus for performing amedical procedure comprises a balloon, which may be non-compliant orsemi-compliant. The balloon may comprise an inflatable body and a firstconnection adapted to maintain the body substantially at a firstdiameter at a first inflation pressure, and to release or disconnect andthereby allow the body to expand to a second diameter. The firstconnection may be released upon a second inflation pressure greater thanthe first inflation pressure being applied to the inflatable body, or bymanual intervention by a clinician.

The apparatus may include a second connection adapted to allow the bodyto assume the second diameter, such as by disconnecting second and thirdportions of the balloon (or possibly associated with the first andsecond portions as well). The second releasable connection mayalternatively be adapted to allow the body to assume a third diameter,such as for example at a third inflation pressure greater than thesecond inflation pressure or as a result of manual intervention by aclinician.

The releasable connection(s) may take a variety of forms. For instance,the releasable connection may comprise an adhesive, and thus may beconsidered a form of a frangible connection. The connection may alsocomprise a first connector connected to the first portion and a secondconnector connected to the second portion and adapted for releasablyengaging the first connector. The connection may also be provided in theform of a retainer with interdigitated portions for maintaining theballoon a desired configuration, such as at a first diameter. A line,such as a cord, may also be provided for releasing the releasableconnection from a remote location, which line may extend though a lumenin a catheter shaft associated with the balloon.

According to a further aspect of the disclosure, an apparatus forperforming a medical procedure includes a balloon comprising aninflatable body having a first fold held in place by a first connectionadapted to release the fold upon the body being inflated. The firstreleasable connection is adapted to release the first fold upon the bodybeing inflated to a predetermined inflation pressure. Thus, the body maybe inflated to provide a first diameter prior to the release of the foldand a second diameter upon release of the fold.

The balloon may comprise a plurality of folds, each held in place by areleasable connection. Each releasable connection may be adapted torelease the corresponding fold upon the body being inflated to adifferent inflation pressure. Alternatively, each releasable connectionmay be adapted to release the corresponding fold upon the body beinginflated to a predetermined inflation pressure.

The first releasable connection may be adapted to hold the first fold inplace while the balloon is inflated to a nominal or first diameter fortreatment. The first fold may include a recessed portion betweenadjacent lobes, each of the lobes including a portion of the releasableconnection.

According to a further aspect of the disclosure, an apparatus forperforming a medical procedure is provided. The apparatus comprises anon-compliant or semi-compliant balloon having a first, substantiallyconstant diameter corresponding to a first range of inflation pressuresand a second diameter, which may be substantially constant,corresponding to a second inflation pressure greater than the firstrange of inflation pressures.

The balloon may further include a third diameter, which may also besubstantially constant, corresponding to a third inflation pressuregreater than the second inflation pressure. The balloon may comprise afirst releasable connection adapted for retaining the balloon at thefirst diameter until the second inflation pressure is reached.

According to a further aspect of the disclosure, an apparatus forperforming a medical procedure comprises a balloon comprising aninflatable body having a fold held in place by an adhesive. Thedisclosure is also considered to pertain to methods of treatment usingany apparatus disclosed herein.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

Reference is made below to the following drawing figures, which are notto scale and provided for purposes of illustration only:

FIG. 1 is a cutaway perspective view showing one embodiment of a balloonto which this disclosure may be applicable;

FIG. 2 is a cross-sectional view of the balloon of FIG. 1 along line2-2;

FIG. 3 is a perspective view of a catheter including the balloon of FIG.1;

FIG. 4 is an alternate embodiment of a catheter including the balloon ofFIG. 1;

FIG. 5 is a schematic end view of a balloon according to one aspect ofthe disclosure, inflated to a first inflation pressure;

FIG. 5a is a close-up cutaway view of the balloon of FIG. 5;

FIG. 6 is a schematic end view of the balloon of FIG. 5 in a fullyinflated condition;

FIGS. 7-9 are schematic end views of balloons showing the reaction to aprogressive increase of inflation pressures;

FIG. 10 illustrates a further embodiment of an adjustable diameterballoon;

FIG. 11 illustrates still another embodiment of such a balloon;

FIGS. 12-16 illustrate further embodiments of various types of frangibleor releasable connections for forming an adjustable diameter medicalballoon.

DETAILED DESCRIPTION

The invention disclosed pertains to an inflatable balloon for performinga medical procedure. The novel features of the invention are set forthwith particularity in the claims that follow. A better understanding ofthe features and advantages of the invention will be obtained byreference to the following detailed description that sets forthillustrative embodiments, in which the principles of the invention areutilized, and the accompanying drawings.

Provided is a catheter 10 having a distal portion 11 with a balloon 12mounted on a catheter tube 14. Referring to FIGS. 1, 2, and 3, theballoon 12 has a body 13 including an intermediate section 16, or“barrel” having the working surface W, and end sections 18, 20. In oneembodiment, the end sections 18, 20 reduce or taper in diameter to jointhe intermediate section 16 to the catheter tube 14 (and thus sections18, 20 are generally termed cones or cone sections, and the barrelprovides the working surface W). The balloon 12 is sealed to cathetertube 14 at balloon ends (proximal 15 a and distal 15 b) on the endsections 18, 20 to allow the inflation of the balloon 12 via one or moreinflation lumens 17 extending within catheter tube 14 and communicatingwith the interior of the balloon 12.

The catheter tube 14 also includes an elongated, tubular shaft 24, whichmay form a lumen 23 that directs the guidewire 26 through the catheter10. As illustrated in FIG. 3, this guidewire 26 may be inserted througha first port 25 of a connector, such as a hub 27, into the lumen 23 toachieve an “over the wire” (OTW) arrangement, but could also be providedin a “rapid exchange” configuration in which the guidewire 26 enters thelumen through a lateral opening 14 a closer to the distal end (see FIG.4). A second port 29 may also be associated with catheter 10, such as byway of connector (hub 27), for introducing a fluid (e.g., saline, acontrast agent, or both) into the interior of the balloon 12 via theinflation lumen 17.

Balloon 12 may include a single or multi-layered balloon wall 28. Theballoon 12 may be a non-compliant balloon having a balloon wall 28 thatmaintains its size and shape in one or more directions when the balloonis inflated to a particular pressure or range of pressures (but below arated burst pressure). However, the balloon 12 could be semi-compliantinstead, as described in U.S. Pat. No. 8,900,215. Prior to use, theballoon wall 28 is typically folded to assume an uninflated diameterthat is only slightly greater than the diameter of the catheter tube 14,which thus facilitates insertion into the vasculature.

According to one aspect of the disclosure, the balloon 12, despite beingnon-complaint or semi-compliant, may be adapted for being inflated froma fully folded or collapsed condition to different diameters fordifferent purposes or uses. In one embodiment, and with reference toFIGS. 5 and 6, this may be achieved through the use of one or morereleasable or frangible connections 30 adapted to retain the body 13 ofthe balloon 12 in a first configuration (such as corresponding to afirst diameter) up to a first inflation pressure, and to release andthereby allow the body to assume a second configuration (such ascorresponding to a second diameter). The release may occur upon theballoon 12 being inflated to a second inflation pressure greater thanthe first inflation pressure, or by way of a manual release, as outlinedfurther in the following description. For purposes of this disclosure,“frangible” means readily or easily broken, and is not meant to limitthe type of connection in any way.

The connections 30 are shown as being formed between first and secondportions 28 a, 28 b of the balloon wall 28, which may thus be arrangedto create one or more folds 32. The folds 32 thus provide the balloon 12with a corresponding number of lobes 12 a, 12 b when inflated to thefirst inflation pressure. The folds 32 may extend along all or a portionof the barrel section 16 of the balloon 12, and may form a recessedportion of the balloon, as perhaps best shown in FIG. 5a . In theembodiment of FIG. 5, four connections 30 are provided, thus giving theballoon 12 on inflation a quatrefoil shape in cross-section when thefolds 32 comprise recessed portions, but more or fewer may be provided.It can be appreciated that the length of material of the balloon wall 28forming the fold 32 corresponds directly to the increase in diameterachieved once the corresponding frangible connection 30 is released, andwhich length may be adjusted as desired during the manufacturing processto provide a greater or lesser increase in diameter.

Each connection 30 may comprise a bond adapted to disconnect or release,either from itself or from corresponding parts of the balloon 12, uponthe inflation pressure reaching or exceeding a particular level. Thus,by way of example, the balloon 12 may be inflated from a collapsed orfolded condition (which is normally the case during insertion to atreatment area in the vasculature) associated with no inflation pressureto a first inflation pressure (such as, for example, 6 atmospheres), andreach a first diameter D1 (such as for example 6 mm), as shown in FIG.5. The balloon 12 may thus be used in this condition to treat a vesselhaving a corresponding diameter, which is typically less than thediameter on full inflation (e.g., 5 mm).

Applying a second inflation pressure (e.g., 8 atmospheres) greater thanthe first inflation pressure, or alternatively the pressure at which theconnection(s) 30 would remain intact and maintain folds 32, would thuscause the balloon 12 to expand to a second diameter D2 (e.g., 9 mm, asindicated by reference numeral 12′). In this condition, as can beappreciated from FIG. 6, the folds 32 are disappeared and the balloon 12along the barrel section 16 with the generally cylindrical cross-sectionhas a substantially smooth and uninterrupted surface. This increaseddiameter may be used to treat a vessel having a different diameter(e.g., 8 mm), and may be created in situ during treatment.

Thus, it can be appreciated that, by using the releasable or frangibleconnections 30, a variable or adjustable diameter balloon 12 may beprovided in a relatively simple and inexpensive manner, and which mayeliminate the need for having different balloons corresponding to thetreatment or vessel diameters at issue (5 mm and 8 mm in this example).It can also be understood that the balloon 12 may be characterized as anon-compliant or semi-compliant one designed to have a first,substantially constant diameter at a first range of inflation pressures(e.g., remaining at about 6 millimeters in diameter from 6 atmospheresup to 8 atmospheres), but then have a second diameter (e.g., 9 mm) at aninflation pressure greater than the first range (above 8 atmospheres).The difference in diameters may be considerable (i.e., 6 millimetersversus 9 millimeters, or about 33% different, but possibly less orperhaps even greater). Likewise, the balloon 12 may be considered as onethat has a different cross-sectional shape at different inflationpressures (such as between the quatrefoil shape of FIG. 5 and thecircular shape of FIG. 6).

With reference to FIGS. 7-8, it can be appreciated that the balloon 12may be adapted to expand to more than two diameters, such as by usingdifferent types of connections 30. Thus, for example, FIG. 7 illustratesa balloon 12 expanded to a second diameter D2 (not necessarily the samediameter as D2 in FIG. 6), and indicated by reference numeral 12′. Inthis condition, one fold may be substantially disappeared, as a resultof the application of a first inflation pressure, but three folds 32a-32 c remain intact as the result of connections 30 a, 30 b, 30 c,which thus form bonds that require a force greater than that created bythe first inflation pressure in order to be broken.

FIG. 8 illustrates the situation where the inflation pressure has beenincreased to at least a second level sufficient to break the bondcreated by connection 30 a, which thus allows for fold 32 a todisappear. The balloon 12 is thus expanded to a third diameter D3greater than diameter D2, as indicated by reference number 12″.Connections 30 b, 30 c remain intact, as do associated folds 32 b, 32 c,for so long as the pressure does not rise to a level sufficient to breakthe corresponding bond(s) and thus further expand the diameter.

Additional pressurization to at least a third pressure level higher thanthe level necessary to remove connection 30 a may cause furtherexpansion to a fourth diameter D4, as indicated by reference number12′″. This may involve breaking the bond created by frangible connection30 c, and thus expanding as a result of the unfurling of material of theballoon wall 28 associated with fold 32 c. Fold 32 b remains intactaccording to connection 30 b, which is designed to withstand the thirdinflation pressure (and possibly a range exceeding it). As should beappreciated, frangible connection 30 b could be designed to disconnectat the third pressure level, either instead of or in addition to thedisconnection of connection 30 c.

A frangible-type connection 30 may be provided by applying an adhesivebetween different portions of the balloon 12, such as along the outersurface of the balloon wall 28, to thus form the folds 32. The adhesivemay be provided along some or all of the wall 28, including possiblywithin the material forming the fold 32, which may provide for thedesirable differential pressure reactions in order to achieve thevariable diameters. Multiple connections 30 may also be provided withina fold 32, which could allow for a single fold to provide multiplechanges in balloon diameter.

FIG. 10 illustrates that the releasable or frangible connection 30 maybe associated with a remotely controlled actuator, such as an elongatedcord or line 34. The line 34 may extend along all or part of theconnection 30 and pass along an external surface of the balloon 12though an opening 36 and into a lumen 23 formed by a tube, such as tube24. The line 34 may pass to an external point for manual manipulation bythe clinician (similar to guidewire 26). In this manner, the release ofthe connection 30 and the resulting expansion of the balloon 12 may beactively controlled in situ. Furthermore, the expansion may occurwithout a corresponding change in the inflation pressure.

In one embodiment, the line 34 may be embedded in an adhesive formingthe frangible connection 30, and may thus form a pull or “rip” cord thatfacilitates to release the bond thus created. Alternatively, withreference to FIG. 11, a connector 40 may be provided between the balloonportions and forms the connection 30, which connector may be associatedwith the line 34. Thus, as illustrated, the connector 40 may comprise azipper-like connection, with a first part 40 a being attached to a firstportion of the balloon 12, and a second part 40 b being connected to asecond portion of the balloon, and an actuator 40 c for releasing theconnector 40 connected to the distal end of the line 34. Still anotheralternative is to provide a non-adhesive connector (such as, forexample, an embedded fiber) that forms a connection or bond among partsof the balloon 12 that is simply overcome by pressurization, withoutusing line 34 and without intervention by the clinician (except ofcourse for causing the increase in pressure).

FIGS. 12-14 illustrate another form of releasable connection 50, whichmay be applied to along external surface of the balloon 12, such asworking surface W, in order to maintain one or more folds 32. As can beappreciated from FIGS. 13 and 14, the connection 50 may be establishedby connecting a retainer 52 to the balloon 12, such as to the surface ofthe balloon wall 28 (inner or outer). The retainer 52 includes offsetopenings 54, as perhaps best understood in FIG. 14. Each opening 54 isadapted to receive an interleaving portion 56 when the retainer isattached to the balloon 12 along end portions 58, 60, as well as anintermediate portion 62, and the balloon wall 28 is folded. As can beappreciated, the interleaving portions 56 when interdigitated thus forma loop 62 through which an object, such as line 34, may be inserted. Theline 34 thus holds the retainer 52 in a position to maintain the folds32 in place, until withdrawn (such as from a remote location external tothe body and through a lumen in the catheter).

Upon withdrawal of the line 34 from the loop 62, the retainer 52 mayrelax or expand to release the underlying folds 32 and thereby increasethe diameter of the balloon 12. As can be appreciated, more than onesuch releasable connections 50 may be associated with the balloon 12,such as by being circumferentially spaced. The use of multipleconnections 50 may provide for a single larger diameter on expansion, ormultiple larger diameters, which may be selectively controlled by theclinician to provide the desired adjustability for different diametersof vessels.

FIG. 15 illustrates that the balloon 12 may be provided with areleasable connection 60 in the form of a jacket 62 over the balloon 12,and along the barrel section 16, in particular. The jacket 62 may beprovided with releasably connected sections 62 a, 62 b, which may beconnected by a frangible connection, such as for instance perforations64. Pressurization of the balloon 12 to an inflation pressureinsufficient to break the connection (perforation 64) would thusmaintain the balloon at a first diameter, and further pressurization toa second inflation pressure (such as beyond a range associated withmaintaining the first diameter) would break the connection and thusallow the balloon to expand in situ.

A further embodiment is described with reference to FIG. 16. In thisembodiment, the balloon 12 is provided with one or more outwardlydirected folds 32 (three shown). The releasable or frangible connection70 is established within the folds along the interior of the balloon 12,which may be done during the process of forming the balloon from a sheetof material. The connection 70, which may be an adhesive or the otherforms described herein, is such that pressurization of the balloon 12 toan inflation pressure that is not sufficient to break the connectionwould thus maintain the balloon at a first diameter, and furtherpressurization to a second pressure level (beyond a range) would breakthe connection and thus allow the balloon to expand in situ during aprocedure.

The foregoing discussion is intended to provide an illustration of theinventive concepts, and is not intended to limit the invention to anyparticular mode or form. Any elements described herein as singular canbe pluralized (i.e., anything described as “one” can be more than one),and plural elements can be used individually. Characteristics disclosedof a single variation of an element, the device, the methods, orcombinations thereof can be used or apply for other variations, forexample, dimensions, burst pressures, shapes, materials, or combinationsthereof. Any species element of a genus element can have thecharacteristics or elements of any other species element of that genus.“Substantially” means that the value may vary depending on thecircumstances. The above-described configurations, elements or completeassemblies and methods and their elements for carrying out theinvention, and variations of aspects of the invention can be combinedand modified with each other in any combination (for instance, thevarious connections described can be combined in any manner for use inconnection with a single balloon), along with any obvious modifications.

1. An apparatus for performing a medical procedure, comprising: aballoon comprising an inflatable body; and a first releasable connectionadapted to maintain the body substantially at a first diameter at afirst inflation pressure; a remotely controlled actuator associated withthe first releasable connection, the remotely controlled actuatorserving to disconnect the first releasable connection to allow theinflatable body to expand to a second diameter.
 2. The apparatus ofclaim 1, wherein the body comprises a first portion connected to asecond portion by the first releasable connection.
 3. The apparatus ofclaim 2, wherein the body includes a plurality of lobes when inflated tothe first inflation pressure, the first portion being on a first lobeand the second portion being on a second lobe.
 4. The apparatus of claim1, wherein the first releasable connection comprises a frangibleconnection.
 5. The apparatus of claim 1, wherein the first releasableconnection comprises a first connector associated with a first portionof the balloon and a second connector associated with a second portionof the balloon and adapted for releasably engaging the first connector.6. The apparatus of claim 1, wherein the first releasable connectioncomprises an adhesive.
 7. The apparatus of claim 1, wherein the remotelycontrolled actuator comprises a line connected to the first releasableconnection.
 8. The apparatus of claim 1, further including a cathetershaft supporting the balloon, the catheter shaft including a lumen forreceiving a portion of the line.
 9. The apparatus of claim 1, whereinthe balloon is non-compliant or semi-compliant.
 10. The apparatus ofclaim 1, wherein the first releasable connection comprises a retainerincluding a plurality of interdigitated portions.
 11. The apparatus ofclaim 10, wherein the remotely controlled actuator comprises a lineassociated with the plurality of interdigitated portions.
 12. Theapparatus of claim 1, wherein the first releasable connection isprovided on an inner surface of the balloon.
 13. The apparatus of claim1, wherein the first releasable connection comprises an adhesive.
 14. Anapparatus for performing a medical procedure, comprising: a ballooncomprising an inflatable body having an interior; and a first releasableconnection in the interior of the balloon adapted to maintain the bodysubstantially at a first diameter at a first inflation pressure, and todisconnect to allow the inflatable body to expand to a second diameter.15. The apparatus of claim 14, wherein the balloon is provided with atleast one outwardly directed fold, and the first releasable connectionis established within the fold along the interior of the balloon. 16.The apparatus of claim 14, wherein the first releasable connectioncomprises an adhesive.
 17. The apparatus of claim 14, wherein thereleasable connection comprises a retainer including a plurality ofinterdigitated portions.
 18. The apparatus of claim 14, wherein theremotely controlled actuator comprises a line associated with theplurality of interdigitated portions.
 19. The apparatus of claim 1,further including a catheter shaft for supporting the balloon, the shafthaving a first lumen extending through the catheter shaft and theballoon and a second lumen associated with the remotely controlledactuator.